Study type: In vitro · Status: Evidence verified by machine against declared source

GluN2C/D-containing NMDA receptors enhance temporal summation and increase sound-evoked and spontaneous firing in the inferior colliculus.

The Journal of physiology · 2025

Study scale: Male (n = 18) and female (n = 15) mice aged P30–P66 were used.

Product or molecular entity relationships

VIP: Exact entity relationship. Legacy citation custody associates this source with the catalog record; no product-relevance conclusion is implied.

Public plain-language summary

The published text is limited to the declared source and preserves reported uncertainty. It does not establish efficacy, safety, suitability, or evidence strength.

Research question

Here, we tested whether GluN2C/D‐containing NMDARs mediate NMDAR currents in the IC, as well as the role of these receptors in synaptic integration and sound processing.

Study design

Consistent with this, we show in vivo that blocking GluN2C/D‐containing receptors decreases both the spontaneous firing rate and the overall firing rate elicited by amplitude‐modulated sounds in many IC neurons.

Participants or experimental system

In line with this previous work, we recently found in adult mice that optogenetic stimulation of commissural inputs elicited EPSPs in IC vasoactive intestinal peptide (VIP) neurons that had a significant contribution from NMDARs at resting membrane potential (Goyer et al., 2019).

Study scale

Male (n = 18) and female (n = 15) mice aged P30–P66 were used.

Intervention or exposure

In line with this, during in vivo recordings from awake mice, local infusion of a GluN2C/D‐specific antagonist decreased spontaneous and sound‐evoked firing rates in many IC neurons.

Comparator

These receptors are less susceptible to Mg2+ blockade compared to GluN2A/B‐containing NMDARs, allowing ions to flow at resting membrane potential.

Outcomes examined

Here, we report the widespread expression of Glun2c and Glun2d mRNA in IC neurons.

Key findings

In addition, GluN2C/D‐containing receptors have much slower kinetics than other NMDA receptors, and we found that GluN2D‐containing receptors facilitate temporal summation of synaptic inputs in vasoactive intestinal peptide neurons.

Limitations and uncertainty

Additionally, although we show here that many NMDARs on VIP neurons contain the GluN2D subunit, the full subunit composition of the receptor remains unknown.

Product relevance and evidence boundary

This record is a published study, held here with its citation and review status. It is not a statement that any catalog item is effective, safe, or suitable for any use, and nothing in it is a dose or a protocol.

Evidence verified by machine against declared source. Verification is limited to the declared source and review scope. It does not mean independent replication or establish efficacy, safety, or suitability.